This invention relates to preparation of 1,1,1-trifluoro-3-chloro-2-propene (1233zd) with reduced oligomer formation ("reduced oligomer formation" referring to less than about 3 weight % oligomer formation) by the catalyzed liquid phase fluorination of 1,1,3,3-tetrachloro-2-propene (1230za) wherein 1230za is contacted with hydrogen fluoride ("HF") in the presence of a catalyst selected from trifluoroacetic acid ("TFA") or trifluoromethanesulfonic acid ("triflic acid"). The 1233zd product is a known intermediate for producing 245fa, as taught, for example, in U.S. Pat. Nos. 5,616,819 and 5,895,825.
U.S. Pat. No. 5,616,819 discloses that previous attempts to fluorinate 1230za to 1233zd in a catalyzed liquid phase reaction resulted in the formation of a reaction mixture contacting primarily oligomeric products.
U.S. Pat. No. 5,877,359 discloses an uncatalyzed liquid process for fluorinating 1230za to 1233za with reduced oligomer formation, but such a process requires high HF:1230za molar ratios and the use of high temperatures and/or long reaction times.
It is thus an object of this invention to provide a catalyzed process for producing 1233zd with reduced oligomer formation.